Generally, steering column locking devices using smart keys have key knob rotation restricting functions and key interlock functions.
The key knob rotation restricting function is conducted through the following process. After a wireless certification process for an available key or an ID card is completed, a control unit operates a solenoid to allow rotation of the key knob such that an engine can be started. When the key knob is moved to a lock position to turn off the engine, the control unit operates the solenoid to restrict the rotation of the key knob such that the steering column enters a locked state.
The key interlock function is conducted through the following process. In the state in which the wireless certification is completed and the engine is started, if a gear shift lever is not in a parking range, the key knob is prevented from moving to the lock position through the operation of the solenoid. Once the gear shift lever enters the parking range, the key knob is allowed to enter the lock position.
However, the conventional steering column locking device having the above-mentioned structure has a problem in that, if a malfunction of the solenoid occurs, the key knob cannot be prevented from entering the lock position even when the vehicle is moving. Furthermore, when the vehicle travels at a high speed, if the key knob is undesirably moved to the lock position, and the steering column thus enters a locked state in which it is impossible to steer the vehicle, a very dangerous condition may be caused.
Furthermore, the conventional steering column locking device must receive information about the gear shift lever in order to conduct the key interlock function. Therefore, in automatic vehicles, because it is possible to determine whether the gear shift lever is in a parking range using a parking range detecting switch, the key interlock function can be used. However, because a manual vehicle is provided with no separate means for detecting the parking range, the key interlock function cannot be used.
In manual vehicles, the key knob is generally prevented from undesirably moving to the lock position when the vehicle is moving using information about the speed of the vehicle. However, only when the key knob is in an ignition ON state, can the information about the speed of the vehicle be used. Therefore, if the key knob is in an accessory position, no information about the speed of the vehicle is obtained. Thus, the key interlock function cannot be conducted.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.